Track for high-speed suspension railways



MaTy 1.1928; 13368511 F. KRUCKENBERG ET AL TRACK FOR HIGH SPEED SUSPENSION RAILWAYS Original Filed Jan.24, 1925 2 Sheets-Sheet 1 F. KRUCKENBERG ET AL TRACK FOR HIGH SPEED SUSPENSION RAIL-WAYS Original Filed Jan. 24, 1925 X A s: L

Patented May l, 192%.

QumransrAT-ss PATENT OFFICE;

FRANZ KRUCKENBERG AND C'URT STEDEFELD, OF HEIDELBERG, GERMANY; SAID STEDEFEILD ASSIGNOR SAID KRUCKENBERG.

TRACK FOR HIGH-SPEED SUSPENSION RAILW'AYS.

Original application filed January 24, 1925, Serial No. 4568, now Patent No. 1,659,322, dated February 14, 1928, and in Germany October 25, 1924. Divided and this application filed. March 5, 1927. Serial The invention concerns a high speed suspension railway for suspension cars travelling with ver great velocity, the construction and arrangement of the permanent way for this railway. Further the invent1on is concerned with the materials, design and construction of the rail itself and. the methods of supporting it. Further the invention is concerned with the details of the supporting means and also the construction works and steel work on which the rail supports are fixed.

i The rail itself must in this invention the protected against variations of temperature, for example housed in a tunnel or tube or constructed of a material which is in it self as far as possible indifferent to temperature changes, such as lnvar whose expansion-coefficient for temperature is so small as to be practicallynegligible. Since all shocks on the car must be avoided at this high speed the rail must have throughout its whole length an. absolutely smooth surface and must be made. of a material which will not rust and which is unafiected by atmospheric influences. Unevennesses or jointspaces which are present in the ordinary railway would at the great speed have a serious effect not only on the rail but also on the unsprung parts of the running-gears of the cars. Since small inequalities of the track are in practice unavoidable the rail must be supported in an elastic manner and at the same time those portions of the track which must give beneath the weight of the car must be kept as light as possible; that is, the rail itself and the parts immediately adjacent which must give sufliciently quickly under the shock. Those unavoidably heavy parts such as the adjustment arrangement for the rail brackets may advantageously be transferredto points which give very little in the elasticmovements of the system, lhe reason for this is that the inertia of an oscillating mass as is well known isdependent on the product of the mass and the square of its velocity.

In order to avoid shocks in this invention the rail ends at the joint points are clamped together so firmly that the longitudinal and .by excessive distortion due to bending. At

these points the pressure between the rail ends must be sufiicient to prevent a plastic flow of the material.

Two methods of carrying this into effect arehere given. Firstly, by means of clamping horizontally the rail ends together with extraordinary high pressure. Secondly, the surfaces of contact at therail ends are confined to those regions respectively near the head and foot of the rail, the intervening material being out awayso that in pressing the rails together only the upper and lower areas come into contact. In this way, of the whole rail faces at the joints, only those areas immediately in the neighbourhoodof the head and foot are brought into contact. This is allowable because the stress caused by the contact of the wheel is extremely local and a great advantage is thatihigh pressure between the rail ends can be obtained without having to exert unreasonably great forces in the apparatus for applying the necessary pressure.

Since the rail material is not cheap it is reasonable to consider a rail made up from several different parts and only to retain in Invar or similar alloy-steel those parts i. e. the upper and under part of the rails the unbroken continuity of which must be preserved. The upper and lower running surface can be of metal of very small section and joined by a very thin web. The strength of this very weak rail section is increased by heavier section pieces of ordinary steel fastened to it in such a way as m give it suilicient strength to carry the weight of the car. a i

Since the jointless rail of temperature-indifferent material remains suspended without any. appreciable expansion or contraction the girderwork being of ordinary inaterial must be constructed in such a manner as to be free to expand and contract independently of the rail.

The invention is illustrated diagrammatically and by way of example on the accompanying drawings, on which Figure 1 is a perspective view of two contacting rail-ends; Figures 2 and 3 are similar views showing two modifications, Figure l is a side-view of two contacting rail ends, this figure being drawn to a reduced scale, Figure 5 is a crosssection in the plane A E and Figure 6 a crosssect-ion in the plane BB of Fig. l, their scale being that of Fig. i, Figure 7 is a View similar to Fig. 4 showing a modification, Figure 8 is a horizontal longitudinal section through the rail portions shown in Fig. 7.

Fig. 1 shows two corresponding rail ends of which the faces touch only at the head and foot of the rail of which the intermediate parts of the faces have been,.cut away so as to keep them out of contact. W hen these rail ends are firmly pressed together the effect of the pressure produced is confined to the limited areas of contact, respectively in the neighbourhood of the head and foot of the rail which means that the pressure is much greater than if the intervening material at a had not been cut away.

A second arrangement of the joint faces is shown in Fig. 2 in which on the one rail Z) the upper contact-area c and the lower contact area (Z project a certain amount while on the other rail 6 the upper contact-area 7 and the lower contact-area g are recessed into the face a corresponding amount. In

this manner the joint faces are constrained against sliding vertically relative to each other.

The third method is shown in Fig. 3. In this method the contact areas are formed by turning or milling the rail ends as is shown at h and i in Fig. 3. By this arrangement in addition to the vertical relative location of the rail ends a certain amount of horizontal adjustment is provided for.

For thejoints of the rail which also exert a pressure between the rail ends hereinafter called compression-joints several kinds of construction will now be described.

For an unbroken continuity of running surface in which the joint-spaces have been so. to speak eliminated by forcing together the rail ends it is naturally assumed that the rail-material is such as not to expand to any appreciable extent with increase of temperature. To this end the rail-material must be, for example, of high-percentage nickel-steel such as so called. Invar, which has a coet'icient of expansion so small that changes in length of the rail due to considerable temper ature variation are so small as to be practically negligible. If one however constructs the railway under the ground for example,

in a tunnel or concrete tube, appreciable temperaturewariation need not be anticipated and so the necessity to make the rail of highclass steel with a low coefficient of expansion no longer exists. 7

Figs. 4 to 6 show in side elevation and two sections an arrangement of compression joint in which thecompressing members are separated from the side-plates k which take the bending moment. The side plates lo are of such section that between them and the rail web exists a free space in which is located the bar Z serving for the horizontal compression. On one end, the tension-bars Z are fastened to the rail by the bolts m. On the other rail are fixed short bars a by means of the bolts 0. The compression of the joint is effected through the screw p. with left and right hand threads which engage with the angles 9. For clearance past the fishplatebolts slots 7 are provided in the tension bars.

In actual practice the bars Z and screw 10 will be formed of the same material as the rail, that is of steel which has a low coefficient of expansion.

In orderto compress the joint-faces s the tension-bars. are firmly contracted together by means of the screws 79. The fish-platebolts are thentightened so that the friction on the rail of the fish-plates assists in holding together the compression-faces.

In Figs. 7 and 8 (side View and longitudinal section seen from above) are shown the side plates used themselves as the tensionbars. Here the side plates 6 on the one rail are fixed by means of fitting bolts to, while on the other rail side pieces 4) are fastened by means of the fitting bolts w. In order to compress together the contact faces 3, on either "side of the rail are arranged wedge plates as, which by being drawn together by means of the bolts y compress the rail faces. The bolts 2 in the other end of the side plates are in slots in the web. of the rail faces and have been clamped together.

The fish plates will be made of the same material as the rail in order to avoid release of the joint due to the effect of different coeflicients of expansion.

We claim 1. A track for high-speed suspension-railways comprising a plurality of rails, and means maintaining the abutting ends of the rails in contact under a longitudinal pressure sufiicient to prevent the said rail ends from separating from wheel pressure and temperature variations, said rail-s being formed of a metal having a temperature expansi'on coefiicient of an order materially lower-"than that of steel.

2. The invention as set forth in claim 1, wherein the rails are formed of a nickel-iron alloy having an approximately zero temperature-resistance coefficient.

3. A track for high-speed suspension ion railways of the kind described, comprising, in combination, a line of rails, fish-plates at the joints, and rail end connecting members between the fish plates and the rails; the individual rails being pressed against one another at the joints in longitudinal direction under such pressure, that'the effect of the wheels running over these joints does not diii'er materially from the effect of the wheels upon the rails at the continuous portions thereof.

4%. A track for high-speed suspensionrailways of the kind described, comprising, in combination, a line of rails, fish-plates at the joints, and rail end connecting members between the fish plates and the rails; the individual rails consisting of a kind of steel having a lesser degree of expansion than ordinary steel and having a thinner web than ordinary rails, the fish-plates con sisting of ordinary steel, substantially as set forth.

5. A track for a high-speed suspensionrailway of the kind described, comprising,

in combination, a line of rails, fish-plates at the joints, and rail end connecting means between the fish-plates and the rails, said means pressing the individual rails against one another at their joints in longitudinal direction, substantially as set forth.

6. A. track for high-speed suspensionrailway of the kind described, comprising,

contact surfaces of the adjacent rail comprise the walls of recesses formed in the end of said adjacent rail.

8. A track for higl1-speed suspensionrailways of the type stated, comprising a line of rails, fish plates at the rail joints, and

tension members for holding adjoining rail ends together under longitudinal pressure.

9. The invention as set forth in claim 8, wherein said tension means comprises tension members secured at opposite sides of" each rail adjacent the joint, and turnbuckles connecting the adjacent ends of the members at the res ective sides of the rails.

In testimony whereof we affix our signatures.

FRANZ KRUCKENBERG. CURT STEDEFELD. 

